Engine control



Jan. 8, 1963 E. A. WACHSMUTH 3, 7

ENGINE CONTROL Filed Feb. 24, 1960 2 Sheets-Sheet 1 FIG. I.

INVENTORI ERICH A. WACHSMU] H BY-WW ATTORNEY ENGINE CONTROL 2 Sheets-Sheet 2 SWI CRIZ

Filed Feb. 24, 1960 Fl G. 3.

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i I v/wzv/ a a m m a 74v//// 7 ATTORNE Y 3,h72,3l Patented Jan. 8, 1%53 free 3,072,315 ENGINE CGNTROL Erich A. Wachsrnuth, Michigan Qty, Ind, assignor to Joy Manufacturing Qornpany, Pittsburgh, Pa, a corporation of Pennsylvania Filed Feb. 24, was, Ser. No. 10,692 '7 (Ilairns. (Q1. 23tl56) This invention relates to an engine control and more particularly to an engine control for starting a free piston engine pump of the counterstroke type.

In an opposed piston, counterstroke engine, the work stroke of one pair of opposed pistons causes the compression stroke of another pair of pistons and vice versa. When a free piston counterstroke engine is stopped, the at rest position of the piston systems is determined by the prevailing equilibrium conditions to which the interconnected pistons are subject. Because of their mechanical interconnection, however, the at rest position of any one piston determines the at rest position of the other pistons. Otherwise the piston may come to a stop at any position within their normal stroke but in proximity of their normal dead points. The latter is prevented by the compression pressure alternately prevailing in one of the engine cylinders and its rebouncing effect.

Accordingly, before such an engine can be restarted it is necessary to move the piston systems to the start position which is about identical with the dead point position of the operating machine. Out of this position the unit then can be started by a sudden release of power, as for example the ignition of a powder charge fired into the small combustion space between adjacent diesel pistons or a sudden admission of pressurized fluid to the pumping chambers of the inwardly moving piston system.

In accelerating the outwardly positioned pistons toward each other, the air trapped between the inwardly moving engine pistons is compressed so that together with the fuel injected toward the end of the stroke it can perform the first diesel ignition, succeeded by the first diesel (power) stroke. Thereafter the operation of the free piston counterstroke engine is self-sustaining until stopped again. At the present it is known to properly locate the pistons of such an engine by various hand operated mechanical means, however, such hand operations are undesirable in many installations and are impossible in installations where such an engine is located remotely from the desired starting location.

Accordingly, it is one object of this invention to provide a control circuit for starting a free piston engine of the counterstroke type.

A further object of this invention is to provide synchronized means for sequentially unbalancing the piston system of a free piston engine pump to provide suificient energy to enable the engine to perform its first power stroke.

Another object of this invention is to provide apparatus for starting the engine of a counterstroke free piston engine pump having means to move the pistons in spaced cylinders in opposite directions which piston movement actuates means to cause the pistons to subsequently move in directions opposite their first directions of movement to prepare the engine to make a power stroke.

These and other objects of this invention will become more apparent upon consideration of the following detailed description of a preferred embodiment thereof, when taken in conjunction with the following drawings, in which:

FIG. 1 is a partial side elevational and partial cross sectional view of a free piston engine pump;

FIG. 2 is a schematic diagram of the starting system for the engine pump as related to one pair of connected pistons in the engine pump shown in FIG. 1;

FIG. 3 is a schematic diagram of an electrical system for controlling certain of the control components shown in PEG. 2.

Referring to FIG. 1, a free piston engine pump comprises a frame F in which a pair of adjacent substantially parallel motor cylinders 1, 1 are located. Each motor cylinder 1, 1 has a pair of opposed pistons 4, 5 reciprocable in counterstroke relation therein, the movement of which pistons 4 and 5 controls scavening slots 2 and exhaust slots 3 located in the Walls of the motor cylinders 1, 1' within which they are located. The pistons 44 and 55 are coupled in pairs by means of elongated double armed rockers 6 and 7, respectively, so that the outward travel or the working stroke of one pair of pistons 4-5 in one cylinder occurs with the inward compression stroke of the other pair of pistons 4, 5 in the other cylinder and vice versa. The rockers 6 and 7 are pivotally supported on the frame F by rocker shafts 8 and 9 and are connected to each other by means of integral intermeshed gear segments 1t and 11 respectively, to maintain all the pistons 4 and 5 in synchronism. The outer ends of each rocker 6 and 7 are provided with suitable cooperable bearings 24 and pins 25 which are supported in block elements 26 which block elements 26 are slidable in suitable guides 27, respectively.

In addition, the frame F has elongated pump cylinders 28 located outwardly adjacent the ends of the motor cylinders 1, 1, respectively, which are coaxial with and open towards the adjacent cylinders 1 or 1'. Each of the cylinders 28 has a piston 12 reciprocably mounted therein, which is rigidly connected to the motor piston 4 or 5 adjacent thereto by means of a suitable elongated conecting rod 33. Each rod 33 has a guide 27 rigidly connected thereto so that the shafts 8 and 9 have an oscillating motion in response to the alternating reciprocating movement of the piston pairs 4-5. For a more complete description of the operation of such a free piston engine, reference is made herein to Patent No. 2,841,322 and Re. Patent No. 24,522.

As described hereinafter, the pump pistons 12 periodically pump any suitable fluid, which for the purposes of describing this invention shall be considered as a hydraulic fluid, from the pump cylinders 28 through chambers 30 located in the frame F outwardly adjacent each of the pump cylinders 28 of the motor cylinders 1 and 1', re spectively. In order to admit and discharge fluid from the chambers 30 (PEG. 2), each chamber 319 has a suitable suction or inlet valve 32 and a suitable discharge valve 33 connected thereto. scribing this invention only the control circuit and the cooperating structure of the engine-pump will be described as shown in FIG. 2. Such suction and discharge valves are well known and any suitable type may be employed such as the ones more fully shown and described in patent application Serial No. 42,363 filed concurrently herewith which application has been assigned to the same assignee as the assignee of this invention. In addition, chambers 41 are located outwardly adjacent the valve 32, respectively, to permit fluid flow to the chambers 30 under the control of the valve 32. Similarly, chambers 42 are provided outwardly adjacent the valves 33, respectively, for receiving fluid from the chambers 30 under the control of the valves 33. Again Serial N0. 42,363 is referred to for a more complete showing and description of the chambers 41 and 42. It is to be understood that chambers 41 and 42 are part of the respective manifold system, however, the designations are descriptive and may well be part of valves, respectively, or conduits.

Fuel is supplied to the motor cylinders 1, 1' by a suitable fuel control device having a pair of fuel injection pumps (not shown) which are of a form wherein the quantity of fuel delivered is adjusted or varied in accordance with well known metering means. Again Patent For the purpose of initially de-- No. Re. 24,522 is referred to for a more complete description of the structure for supplying fuel. In order to vary the delivery of the pressurized fluid from the pump cylinders 28, the inlet valves 32 therefor, respectively, are controlled by a pair of impulse givers (not shown) which are of a structure as is more fully described in Patent No. 2,841,322 and Re. Patent No. 24,522. For the purposes of this invention the impulse givers may be of any suitable structure, however, the structure shown described and claimed in the copending patent application, Serial No. 697,012, filed November 18, 1957 which application has been assigned to the same assignee as this invention, is more particularly suited for this invention and accordingly reference is made thereto to more fully understand the structure and operation of the impulse givers.

As shown in FIGURE 2, a suitable high pressure hydraulic fluid accumulator HPA is suitably connected by suitable conduits 16 and 17 to the chambers 42, respectively, whereby the fluid pumped by pistons 12 is discharged to the high pressure accumulator HPA. A low pressure accumulator LPA is suitably connected by suitable conduits 14 and 15 to the chambers 41, respectively, whereby fluid can flow from the low pressure accumulator LPA to the chambers 4-1. A suitable normally open solenoid operated valve V1 is connected in the conduit 14 for controlling the flow of fluid from the low pressure accumulator LPA to one of the chambers 41 as hereinafter described. A suitable normally open solenoid operated valve V2 is connected in the conduit 15 for controlling the flow of fluid from the low pressure accumulator LPA to the other chamber 41. in order to vent the chambers 3t as hereinafter described, passageways 45 and 46 are provided which extend through the frame F from the chambers 30, respectively, which passageways 4S and 46 are connected to suitable conduits 43 and 4-4, respectiveiy. The conduits 43 and 44 are connected to a suitable reservoir R and are provided with suitable normally closed solenoid operated valves V3 and V4 respectively as are well known in the art.

In order to obtain the desired starting of the engine pump in accordance with the principles of this invention, it is necessary to sequentially operate the various solenoid operated valves heretofore described. FIGURE 3 illustrates an electric control circuit for so actuating the valves V1, V2, V3 and V4; however, it is to be realized that the circuit shown is only one suitable control circuit and if desired other control circuits can be employed for controlling the various valves. As shown the control circuit comprises a suitable source of direct current, such as a battery B, the opposite sides of which are connected to suitable spaced electric conductors 50 and 51 respectively. A suitable electric conductor 52 is electrically connected to the conductors 50 and 51 which has a suitable starting switch SSW for the operating coil CR1 of a relay connected in series therein so that upon closing of the switch SSW the coil CR1 is electrically energized. The switch SSW is of a suitable structure so that after initiation of the energization of the coil CR1 it is returned to its open position, which structures are well known in the art. A suitable electrical conductor 53 is connected to the conductor S and to the conductor 52 between the switch SSW and the coil CR1. The conductor 53 has a suitable electric switch RSW1 and a pair of relay contacts CR11 connected in series therein. With such a structure when the switch SSW is closed the energization of the coil CR1 causes the relay contacts CR11 to close so that, when the switch RSWl is closed, the coil CR1 is constantly energized until the switch RSWI is sequentially opened. For the purposes of this invention the switch RSWl, as is the switch RSW2 hereinafter described, is normally closed. The relay coil CR1 also actuates a pair of relay contacts CR12 which are connected by means of a suitable electric conductor 54 to the conductor and to a pair of parallel suitable electrical conductors 6'1 and 62 which have the operating coils of the valves V2 and V4 electrically connected therein, respectively, and which conductors 61 and 62 are connected to the conductor 51. The coils of the valves V2 and V4 are energized upon the closing of the switch SSW as more fully described hereinafter.

It will be noted that the above described portion of the electric control circuit is duplicated to provide for operating the coils of the valves V1 and V3. Thus a switch RSW2 is connected to the conductor 50 in parallel with the switch RSW1 with respect to the battery B. A suitable electrical conductor 55 having a pair of relay contacts CRM and the operating coil of a relay CR2 connected in series therein is connected to the conductor 50 so that the switch RSW2 is connected in series with the conductor 55 and the battery B. The conductor 55 is also connected to the conductor 51 so that upon closing of the contact CR31 and with the switch RSW2 being closed, as is its normal position, the relay coil CR2 is electrically energized. Energization of the operating coil CR2 causes closing of a pair of contacts CR21 connected to the conductors 5t? and 55 in parallel with the contacts CR31. Energization of the operating coil CR2 also causes closing of a pair of contacts CR22 connected by a conductor 56 to the conductor 5%) so that the switch RSW2 is located between the conductor 56 and the battery B. The conductor 56 is also connected to a pair of parallel conductors 57 and 58 having the operating coils of valves V1 and V3 therein, respectively, which conductors 57 and 58 are also connected to the conductor 51.

in order to obtain energization of the operating coil CR2 an additional relay operating coil CR3 is connected by means of a conductor 59 to the conductor 52 so as to electrically parallel the operating coil CR1. It will be noted that the conductor 59 has a suitable electrical rectifier RE connected therein to prevent current flow through the coil CR3 when the operating coil CR1 is electrically energized by the battery B. Upon opening of the switch RSWl, as hereinafter described, the coil CR1 is electrically deenergized so that during the deenergization period a back current flow through the coil CR3 occurs which energizes the coil CR3 whereby the contacts CR311 are momentarily closed, which causes the energization of the coil CR2 and the closing of the holding switch C1121, providing the switch RSW2 is closed as hereinafter described. Inasmuch as the various operating coils and contact structures for relays are well known in the art the mechanical linkages and contacts have not been shown.

As will become apparent hereinafter, the switches RSWI and RSW2 are of any suitable structure which are normally closed and which can be opened as desired by any suitable mechanical or electrical means. For the purposes of this invention the switches RSWl and RSW2 are sequentially operated upon the sequential movement of the pistons 4. Specifically the switch RSWI is opened in the proximity of the inner dead point of one of the pistons 4. The switch RSW2 is opened in the proximity of the inner dead point of the other piston 4 respectively. In view of the fact that such opening and closing of the switches RSW1 and RSW2 can be accomplished in a wide variety of mechanical and electrical means, the particular structure and location of the switches RSWl and RSW2 is only illustratively shown by structure lines L.

In starting the engine pump various conditions may exist with relation to the pressures in the high pressure accumulator HPA and the low pressure accumulator LPA; however, to best described this device it will be assumed that a sufficient pressure exists in the low pressure accumulator LPA to accomplish the initially described operation. As shown in FIGURE 3, with a sufficient pressure existing in the low pressure accumulator LPA and with the valves V1 and V2 being in their normal open position, the pressurized medium in the low pressure accumulator will cause a uniform pressure to exist throughout the entire fluid system exclusive of the high pressure accumulator HPA and the connections thereto. With the pressures balanced in both cylinder systems 28 the piston system could be located at any point within the stroke. Gas pressure acting on the engine pistons at the moment the engine is stopped by cutting off the fuel and the discharge pressure conditions at this very moment prevent a stop in the proximity of the normal return points. To start the engine pump the switch SSW is closed so that current from the battery B flows from the battery B through the conductors 59 and 52, having the closed switch SSW therein and the coil CR1 therein, to the conductor 51 to electrically energize the coil CR1. Upon such energization the contacts CR11 are closed and since the switch RSWl is normally closed, a holding circuit for the coil CR1 is established through the conductors 5t 53, 52 and 5-1. Energization of the coil CR1 also closes the contacts CRlZ so that the operating coils of the valves V2 and V4 are electrically energized from the battery 13 through the conductors 50, 54, 61 and 62 in parallel, and conductor 51. Upon energization of the coils of the valves V2 and V4 the valve V2 is closed and the valve V4 is opened. Under these conditions the pressure from the low pressure accumulator LPA is not efiective in the conduit 15 and the right chamber 3%. (The terms left and right are employed herein to simplify the description of operation; however, they have no essential relation to the structure of the device and relate only to FIG. 2.) Since the right chamber 39 is vented to the sump R no pressure will exist therein higher than the sump pressure. At the same time the fluid from the low pressure accumulator LPA exerts, through the conduit 14, the left chamber 41, the left inlet valves 32 and the left chamber 30, a force on the left piston 4 whereby the force exerted on the pistons 4 is unbalanced and the left piston 4 is driven on an in ward stroke. Such movement of the left piston 4 continues until the full inward stroke is achieved at which time the switch RSWl is opened.

Upon opening of the switch RSWI the holding circuit for the coil CR1 is broken since the switch SSW is open so that the contacts CRM and CRlZ open. Opening of the contacts CR12 deenergizes the coils for the valves V2 and V4 so that the valve V2 returns to its normal opened position and the valve V4 returns to its normal closed position. At the same time the opening of the holding circuit for the coil CR1 causes a back current to flow from the coil CR1 through conductor 59, rectifier RE and the coil CR3 so that the coil CR3 is energized to close the contacts CR31 since the switch RSWZ is in its normal closed position. Closing of the contact CR31 connects the coil CR2 across the conductors 50 and 51 so that contacts CR2 and CR22 are closed. The contact CR21 establishes a holding circuit for the coil CR22 through the conductor 50, the closed contacts CR21 and through the conductor 51. .Similarly the closing of the contact CR22 connects the coils of the valves V1 and V3 across the conductors 50 and 51 by means of the conductors 56, 57 and 58. Upon energization of the coils of the valves V1 and V3 the normally open valve V1 is closed and the normally closed valve V3 is opened. It should be particularly noted that, since a back current is involved in initially energizing the coil CR3, the valves V1 and V3 can readily be energized at an instance slightly later than the opening of the valves V2 and the closing of valve V4 so as to prevent any pressurized fluid from escaping from the low pressure accumulator LPA.

Thus the first movement of the unbalanced piston system results in a changing of the connections to the piston system so that the piston system is unbalanced in the exact reverse manner, i.e. the valve V3 vents the left chamber 39 to atmosphere while the low pressure accumulator LPA is closed from the conduit 14 by the closed valve V1. At the same time the pressure from the low pressure accumulator LPA through the open valve V2 pressurizes the right chamber 30 so that the right piston 4 is driven through its entire stroke from its extreme outer stroke position. Since the right piston 4 was initially in its outward position, such movement of the right piston 4 will insure that a full travel is taken so that the diesel compression is achieved. Full travel can only take place when the mean pressure of this starting stroke times the volume displaced equals the respective diesel compression work plus the expansion work in the counterstroking system (while pulling a vacuum) plus all hydraulic and mechanical losses occurring within this starting stroke. For a more particular description of the diesel compression in such an engine reference is again made to the above identified patents.

Upon complete inward stroke movement of the right piston 4 the switch RSW2 is opened so that the holding circuit for the coil CR2 is deenergized and the contacts CR21 and CR22 opened. Thereafter upon movement of the right piston 4 the control circuit of the valve V3 is returned to its initial condition and is no longer operative until the switch SSW is again manually depressed. It will of course be obvious that unless additional provisions are made to swing the switches out of the travel of the pistons 4 they will be continuously opened and closed. Accordingly, the switches RSWl and RSW2 may be stationarily mounted on the frame F in any suitable manner or may be movably mounted so as to be removable from their actuating means after starting of the engine has occurred.

Although as heretofore indicated the low pressure accumulator has sufiicient pressure to accomplish the above unbalance and moving of the piston 4, it will be obvious that in those cases where the low pressure accumulator may not have suflicient pressure an auxiliary means is used to bring up the pressure in the accumulators to perform the first diesel compression. One means would place a suitable connection between the high pressure accumulator I-IPA and the low pressure accumulator LPA having a manually controlled valve V5 therein. By this structure the pressure in the high pressure accumulator HPA may be equalized upon opening of the valve V5 with the pressure in the low pressure accumulator LPA to obtain the necessary pressure in the low pressure accumulator LPA. The valve V5 is subsequently closed before starting. It will be understood in some instances that valve V5 is not used as the pressures in the high and low pressure accumulators balance relatively quickly after the unit has stopped due to the internal leakage of the system. It will be further understood that where the system has stood unused an unusually long period of time that the accumulators may lose their pressures completely as where there is a defective valve. Thereafter the high pressure accumulator must be pressurized as well as the low pressure accumulator so that there is sufiicient pressure in the system. In any event the low pressure accumulator must have enough pressure to perform the first diesel compression. Where no pressure exists in the high pressure accumulator HPA, an auxiliary source of pressure such as a pump 65) may be connected to the low pressure accumulator LPA to build up the necessary pressure therein for moving the pistons 4. Thus it will be noted that I have provided a system which is suited for remotely starting a free piston engine in which the pistons are first unbalanced in one direction and then unbalanced in another direction which unbalance is under the control of means which is only operative during the starting of the engine. In addition, the accumulator systems are always balanced prior to starting the engine. Although the operation of the starting system has only been described with relation to one pair of outer movable pistons 4, it will particularly be noted (see co-pending application Serial No. 42,363) that the system may be duplicated for each pair of pistons 4 or a single start up system may be employed to drive each pair of pistons simultaneously.

Having described a preferred embodiment of this invention in accordance with the patent statutes, it is to be realized that modifications thereof may be made without departing from the broad spirit and scope of this invention. Accordingly, it is respectfully requested that this invention be interpreted as broadly as possible and as limited only by the prior art.

What I claim is:

1. A starting system for a pump comprising, a frame having cylinders, pistons movably mounted in said cylinders, means for synchronizing the movement of said pistons in opposite rectilinear reciprocation, accumulators connected to said cylinders respectively, valve connections between said accumulators for equalizing the pressure in said accumulators, valve means normally open for connecting one of said accumulators to said cylinders to equalizing the pressures in said cylinders, normally closed vents connected to said cylinders respectively for venting said cylinders to atmosphere upon opening thereof first switch means energizing one of said normally closed vents for venting one or" said cylinders to atmosphere, while simultaneously closing that portion of said valve means connecting the one mentioned cylinder to the accumulator to thereby condition said pistons to move in their respective rectilinear directions, second switch means actuated by movement of said pistons in their said mentioned directions for closing said vent of said one mentioned cylinder while venting said other cylinder and opening that portion of said valve means that connects the one mentioned cylinder to the accumulators while closing that portion of said valve means that connects the other cylinder to the accumulators to thereby move said pistons in respective rectilinear directions which is opposite in direction to their first mentioned direction of movement, third switch means actuated by movement of said pistons in their last mentioned direction of movement for closing said vents and opening said valve means to thereby condition the pump for normal operating conditions.

2. A starting system for a free piston engine pump having at least two power cylinders, a pair of opposed pistons reciprocably mounted in each of said cylinders respectively, connecting means between said pistons for synchronizing the outward strokes of one pair of pistons with the inward strokes of the other pair of said pistons, each of said cylinders having a pair of spaced pump cylinders coaxially therewith wherein each pair of said pump cylinders are located on opposite sides of said respective cylinders thereby presenting a one pair of opposed pump cylinders and another pair of pump cylinders, each pump cylinder has a pump piston reciprocably mounted therein wherein each of said pump pistons are connected to adjacent said coaxially mounted pistons respectively for movement therewith, input means connected to said pump cylinders respectively, energizable control means connected to said input means for pressurizing one pair of said pump cylinders to move said one pair of opposed pump pistons mounted therein inwardly, means responsive to the movement of said last mentioned pair of opposed pump pistons for operatively connecting said energizable control means to said input means for pressurizing said other pair of pump cylinders to move said other pair of opposed pump pistons inwardly to condition the engine for a power stroke.

3. A motor compressor comprising in combination two power cylinders disposed side by side and each having at each of its opposite ends a compressor cylinder mounted coaxially therewith wherein one pair of said compressor cylinders adjacent to one of said power cylinders define a first pair of compressor cylinders while the other pair of said compressor cylinders associated with the other of said power cylinders defines a second pair of compressor cylinders, two pairs of opposed motor pistons, one pair reciprocable in each of said power cylinders, a compressor piston movable with each motor piston and reciprocable in a compressor cylinder respec tively, synchronizing means operatively connected to said pistons for moving one pair of said opposed motor pistons inwardly while moving the other pair of said opposed motor pistons outwardly, said motor compressor having input means operatively connected by control means to said first pair of opposed compressor cylinders while venting to atmosphere said second pair of compressor cylinders thereby moving one pair of opposed motor pistons inwardly, means responsive to said last mentioned inward movement of said one pair of opposed motor pistons for actuating said control means for operatively connecting said input means to said second pair of compressor cylinders while venting to atmosphere said first pair of compressor cylinders thereby moving said last mentioned one pair of opposed motor pistons outwardly to condition the engine for a power stroke.

4. A free piston engine starting system comprising, a frame having a pair of spaced combustion cylinders, a pair of opposed motor pistons reciprocably mounted in each of said cylinders respectively, means connecting said pairs of pistons for movement in opposite directions, additional means connecting said connecting means for synchronized movement for moving said pairs of opposed pistons in counterstroke relationship, each combustion cylinder having a pump cylinder coaxial therewith, a pump piston mounted in each pump cylinder wherein each pump piston is connected to the adjacent said motor piston, input means connected to said pump cylinders respectively, energizable control means operatively connected to said input means for selectively moving one pair of opposed pump pistons inwardly toward each other while moving the other pair of opposed pump pistons away from each other, and means responsive to said movement of said pump pistons for moving said pump pistons in a direction opposite to said first mentioned movement wherein said pistons condition said motor pistons for a power stroke.

5. A free piston engine starting system as set forth in claim 4 wherein said input means comprises accumulators connected to said pump cylinders for supplying compressed fluids to said pump cylinders respectively.

6. A free piston engine starting system as set forth in claim 4 wherein said input means comprises a first accumulator connected to said pump cylinders through inlet valves and a second accumulator connected to said pump cylinders through outlet valves.

7. A free piston engine starting system as set forth in claim 6 wherein said energizable control means includes control valves located between said first accumulator and said pump cylinders for controlling the supply of moving medium to said pump cylinders.

References Cited in the file of this patent UNITED STATES PATENTS Re. 24,522 Wachsmuth Aug. 19, 1958 1,931,164 Lanning Oct. 17, 1933 2,215,326 Janicke Sept. 17, 1940 2,434,877 Welsh et al. Jan. 20, 1948 2,611,233 Welsh Sept. 23, 1952 2,638,266 Meitzler May 12, 1953 2,754,654 Kholucy July 17, 1956 2,795,927 Huber June 18, 1957 2,841,322 Wachsmuth July 1, 1958 2,867,374 Peterson Jan. 6, 1959 

1. A STARTING SYSTEM FOR A PUMP COMPRISING, A FRAME HAVING CYLINDERS, PISTONS MOVABLY MOUNTED IN SAID CYLINDERS, MEANS FOR SYNCHRONIZING THE MOVEMENT OF SAID PISTONS IN OPPOSITE RECTILINEAR RECIPROCATION, ACCUMULATORS CONNECTED TO SAID CYLINDERS RESPECTIVELY, VALVE CONNECTIONS BETWEEN SAID ACCUMULATORS FOR EQUALIZING THE PRESSURE IN SAID ACCUMULATORS, VALVE MEANS NORMALLY OPEN FOR CONNECTING ONE OF SAID ACCUMULATORS TO SAID CYLINDERS TO EQUALIZING THE PRESSURES IN SAID CYLINDERS, NORMALLY CLOSED VENTS CONNECTED TO SAID CYLINDERS RESPECTIVELY FOR VENTING SAID CYLINDERS TO ATMOSPHERE UPON OPENING THEREOF FIRST SWITCH MEANS ENERGIZING ONE OF SAID NORMALLY CLOSED VENTS FOR VENTING ONE OF SAID CYLINDERS TO ATMOSPHERE, WHILE SIMULTANEOUSLY CLOSING THAT PORTION OF SAID VALVE MEANS CONNECTING THE ONE MENTIONED CYLINDER TO THE ACCUMULATOR TO THEREBY CONDITION SAID PISTONS TO MOVE IN THEIR RESPECTIVE RECTILINEAR DIRECTIONS, SECOND SWITCH MEANS ACTUATED BY MOVEMENT OF SAID PISTONS IN THEIR SAID MENTIONED DIRECTIONS FOR CLOSING SAID VENT OF SAID ONE MENTIONED CYLINDER WHILE VENTING SAID OTHER CYLINDER AND OPENING THAT PORTION OF SAID VALVE MEANS THAT 